Figure 1: Flow diagram of the experimental protocol of the study. The purpose of phase 1 was to determine the extent of time it would take for physiological blood parameters of the rabbit synovial tissue to reach a steady state as the temperature of the joint was experimentally forced to change. The devices used in this phase were intraarticular angiocatheters for measurement of blood perfusion (BPU), oxygen partial pressure (pO2) [reference standard measures) and intraarticular temperature at forced increased and decreased joint temperatures. The purposes of phase 2 were to test whether BOLD MRI values change with increased (37-41°Celsius) and decreased local joint temperatures (37-32°Celsius) in relation to corresponding baseline values over the period of time established in phase 1 in 3 different types of joints (arthritic and contralateral knees of injection group rabbits and control knees of non-injection group rabbits) [internal responsiveness]; and to determine whether an association exists between BOLD MRI values (test) and results of intraarticular pO2 and BPU [reference standard measures]. Only one knee per rabbit underwent the temperature change procedures.